Adaptations of plants to availability of water

Waxy cuticle on upper epidermis: reduces e... of water from upper surface of leaf

evaporation

Stomata found on lower epidermis (underneath) leaves: surface = heated directly by sun - reduces e... of water

evaporation

Most stomata closed at night: plants cant p... in the dark

photosynthesise

Deciduous plants lose leaves in winter: water in soil maybe f... (less water available) + temperature may be too low for p... to occur

frozen, photosynthesis

Xerophytes: plants that're adapted to living in very d... conditions

Adaptations:

Close their stomata when water a... = low

Maintain high salt conc in their leaf cells - reduces water potential + w... p... g... between cells + air spaces in leaf - reduces water loss

Very long roots - reach water deep u...

dry, availability, water potential gradient, underground

Marram grass: grows on sand dunes

Hold little w... + can be very s..., very w... conditions

Adaptations:

Leaf r... longitudinally: air trapped inside = h... - reduces water loss from leaf (can roll tighter in very hot/windy conditions)

Thick waxy cuticle: reduces e... of water

Stomata on inner side of rolled leaf - protected - in p... - folded + covered in hairs help reduce a... movement + increase h... - reducing water loss

Spongey mesophyll: very dense - smaller s... a... for evaporation

water, salty, windy, rolled, humid, evaporation, pits, air, humidity, surface area

Cactus: native to Americas

Majority = s... (can store water in their stem, often ribbed/fluted so can e...)

Leaves = reduced to spines - reduces s... a... - limits water loss

Trap moisture - reduces w... p... g...

Stem = green - can p...

Roots = widespread/deep

Close stomata at h... time of day

Store c... d... produced at night by respiration

Very thick w... c...

succulents, expand, surface area, water potential gradient, photosynthesise, hottest, carbon dioxide, waxy cuticle

Hydrophytes: get oxygen via their tissues that're submerged in w... + keep their leaves afloat so in air - can absorb s...

Many large air spaces in leaves - keeps plant a...

Leaf stem - many large air spaces - b... + allows oxygen to diffuse to roots quickly for a... r...

Stomata = on upper epidermis to allow g... e...

F... stems + leaves to reduce damage by water currents

water, sunlight, afloat, buoyancy, aerobic respiration, gas exchange, flexible

Transpiration: loss of w... v... from a... parts of plant

water vapour, aerial

Plants s... in water/live in very h... conditions - challenge

Transpiration needed to absorb water for p... + transport m... i... up to leaves

Hydathodes = specialised structures at t... of leaves - allow water to be released + e... from surface of leaf

submerged, humid, photosynthesis, mineral ions, tips, evaporate